diff --git a/renderer.php b/renderer.php
index f4a217bf728c99295aa6570dfe871f4a7227cb93..f8755ecd8c95fde9df3be996a301a392a44349d6 100644
--- a/renderer.php
+++ b/renderer.php
@@ -367,7 +367,7 @@ class block_course_overview_uwmoodle_renderer extends plugin_renderer_base {
 
         if($useajax){
             $html .= 'block_course_overview_uwmoodle_use_ajax = true;';
-            $html .= 'block_course_overview_uwmoodle_config = "' . json_encode($config) . '";';
+            $html .= 'block_course_overview_uwmoodle_config = \'' . json_encode($config) . '\';';
         }else{
             $html .= 'block_course_overview_uwmoodle_use_ajax = false;';
         }